101Leafy researched the games.
Thunderblade Vajra+

Sword used by a boy raised by the thunder beast. It's made of Kirin horn.
| Class | Sword |
|---|---|
| Rarity | 10 |
| Attack | 350 |
| Thunder | 380 |
| Slots | 2 |
| Price | 120,000z |
Upgrades
| Upgraded from | Thunderblade Vajra |
|---|
Upgrade tree from モンスターハンターポータブル 2nd G 公式ガイドブック (Enterbrain, 2008), page 700.